1) Field of the Invention
The present invention relates to novel 3-substituted vinyl cephalosporin derivatives having excellent activities as medicine.
2) Description of the Related Art
The following derivatives have been known as compounds with a substituted or unsubstituted vinyl group introduced at the 3-position of a thiazolylacetamidecephem derivative.
European Patent Application No. 30630 discloses 7-acylamino-3-vinylcephalosporan derivatives, including compounds represented by the following formula: ##STR2## wherein R is a lower alkyl, lower alkenyl, lower alkynyl or carboxy-lower alkyl group.
Further, Japanese Patent Application Laid-open No. 89089/1984 discloses, as 7-substituted-3-vinyl-3-cephem compounds, compounds represented by the following formula: ##STR3## wherein R.sup.1 represents an amino group or an amino group protected with one or more protecting groups and R.sup.2 represents a carboxyl group or a carboxyl group protected with a protecting group.
On the other hand, Japanese Patent Application Laid-open No. 491/1987 discloses a compound represented by the following formula: ##STR4## wherein R.sup.3 is a hydrogen atom or an ordinary amino-protecting group, R.sup.4 is a hydrogen atom or a linear or branched alkyl group having 1-4 carbon atoms, an alkenyl or alkynyl group having 2-4 carbon atoms, a cycloalkyl group having 3-6 carbon atoms, a cycloalkylalkyl group having a 3-6 membered ring or 4-10 carbon atoms or an alkanoyl group having 2-4 carbon atoms, R.sup.5 is a hydrogen atom or a lower alkyl group having 1-3 carbon atoms, a lower alkoxyl group having 1-3 carbon atoms or a lower alkanoyloxyl group having 2-3 carbon atoms, and R.sup.6 is a hydrogen atom or a physiologically hydrolyzable ester group, for example, an acetoxymethyl, 1-acetoxyethyl, pivaloyloxymethyl, 5-methyl-2-oxo-1,3-dioxolan-4-ylmethyl, 1-(ethoxycarbonyloxy)ethyl or 4-glycyloxybenzoyloxymethyl group.
However, sufficient antibacterial activities are not available from any of these compounds and therefore, there is a strong desire for the development of still more effective derivatives.